Myocardial cell membrane is a semi-permeable membrane, resting state, the membrane arranged a certain number of positively charged cationic, the film lined the same number of negatively charged anion, the membrane outside the potential is higher than the membrane, called the polarization state. Resting state, due to cardiac myocytes in various parts of the polarization state, there is no potential difference, the current recorder of the potential curve straight, that is, the surface electrocardiogram and other potential lines. Myocardial cells in a certain intensity of stimulation, cell membrane permeability changes, a large number of cationic short time into the membrane, the membrane potential by negative change, this process is called the polar. For the whole heart, the potential changes of myocardial cells from endocardial to epicardial sequence in the process of polar removal from the current recorder are known as the Polar Wave, i. e. the P waves and ventricular QRS waves in the atria on the surface electrocardiogram. After the removal of the cell, the membrane is discharged by a large number of cations, the membrane potential from positive to negative, restored to the original polarization state, this process by epicardial to Endocardial, called Repolarization. Similarly, the potential changes in the process of myocardial cell repolarization are called repolarization waves by the current recorder. Since the complex process is relatively slow, the complex polar wave is lower than the polar wave. The complex polar waves of the atrium are low and buried in the polar wave except in the ventricle, and the surface electrocardiogram is not easily recognizable. The complex polar waves of the ventricle are represented by T waves on the surface electrocardiogram. After all the myocardial cells were recovered, the polarization state was restored, and there was no potential difference between the myocardium cells and the surface electrocardiogram recorded to the Equipotential line.